"They have their own people": Emotional connections, community belonging, and Chinese gay, bisexual and other men who have sex with men (GBMSM) college students' needs for sexual health support.

Gay, bisexual and other men who have sex with men (GBMSM) college students in China have unique sexual health challenges, including a higher risk of HIV infection, stigma and discrimination against LGBTQ (lesbian, gay, bisexual, transgender, and queer) population, and limited access to LGBTQ-affirmative sexual health support. Nonetheless, previous research or policymaking has rarely addressed the students' needs for sexual health support from their perspectives. This study aims to explore GBMSM college students' perceptions and attitudes to current sexual health resources, the challenges they encounter, and their expectations to acquiring LGBTQ-affirmative sexual health information and services. The exploration was carried out through field visits and in-depth interviews with 26 GBMSM college students and eight relevant stakeholders in five cities in China. Qualitative thematic analysis was applied to the interview transcripts and fieldwork memos. Four themes emerged around the preference and needs of GBMSM students in dealing with their sexual health challenges: the association between tackling sexual health challenges and entering LGBTQ communities, the roles of emotional attachment in shaping the preference for HIV-related care and support, the desired modes of acquiring sexual health support, and the current unmet service needs. We discovered that the information-and-care-seeking behaviors of GBMSM college students are highly influenced by and connected to their participation in online and in-person LGBTQ communities. Due to the overall stigmatizing sociocultural environment of LGBTQ in China, GBMSM college students tend to rely on LGBTQ communities, seeking trust and a sense of belongingness for tackling their sexual health challenges. Conventional school-based sexual health educational programs, which often apply top-down, stigma-and-fear-based, and non-LGBTQ-inclusive teaching strategies, rarely help GBMSM college students to solve sexual health problems in real life. GBMSM college students are eager to have LGBTQ-affirmative "health managers" who can understand their emotional experiences and interpersonal contexts and assist them with sexual health issues. However, such support is generally perceived as limited by the students. Our study highlights these unmet needs of the GBMSM students and emphasizes the importance of developing future LGBTQ-affirmative sexual health programs among Chinese GBMSM college students and young GBMSM in general.

Investigation on Wire Electrochemical Discharge Micro-Machining.

With the development of MEMS, the machining demand and requirements for difficult-to-machine metal micro parts are getting higher. Microelectric discharge machining is an effective method to process difficult-to-machine metals. However, the recast layer caused by high temperatures in microelectric discharge machining affects the properties of machined materials. Here, we propose the wire electrochemical discharge micro-machining (WECDMM) and develop a new electrolyte system, which removes the recast layer. In this study, the mechanism of WECDMM was elucidated. The electrolyte was optimized through a comparison experiment, and NaNO3-glycol solution was determined as the best electrolyte. The influences of key process parameters including the conductivity of the electrolyte, pulse voltage, pulse-on time and wire feed rate were analyzed on the slit width, standard deviation, the radius of fillet at the entrance of the slit and roughness. Typical microstructures were machined, which verified the machining ability of WECDMM.

Sex and Urban-Rural Differences in the Relationship between Childhood Sexual Abuse and Mental Health among Chinese College Students.

This study aimed to reveal sex and urban-rural differences in the association between childhood sexual abuse (CSA) and mental health among Chinese college students. The study used data from the "National College Student Survey on Sexual and Reproductive Health 2019", a cross-sectional study conducted in all 31 provinces of mainland China. Weighted logistic regression analysis was conducted to determine the association between CSA (noncontact CSA, contact CSA, and penetrative CSA) and mental health (suicide attempts and mental disorders). Among 49,728 students, 39.42% of the male participants and 43.55% of the female participants had ever experienced CSA. According to the OR results of logistic regression analysis, compared to females, males in the contact CSA group (AOR: 3.49, 95% CI: 1.95-6.23) and the penetrative CSA group (AOR: 8.79, 95% CI: 3.15-24.52) had higher odds of suicide attempts. Participants from rural and suburban areas that were categorized in the penetrative CSA group were more likely to report suicide attempts (rural: AOR: 4.01, 95% CI: 1.51-10.62, suburban AOR: 4.86, 95% CI: 2.52-9.36) and mental disorders (rural: AOR: 4.01, 95% CI: 1.51-10.62, suburban: AOR: 4.86, 95% CI: 2.52-9.36). In conclusion, the findings revealed a high prevalence of CSA in both sexes and reported that males are more vulnerable to the adverse effects of CSA. In addition, we also found that undergraduates growing up in rural and suburban areas are more vulnerable to the adverse psychological effects of CSA. Policymakers should pay more attention to this vulnerable population and implement effective measures to alleviate mental trauma.

Increasing large wildfires over the western United States linked to diminishing sea ice in the Arctic.

The compound nature of large wildfires in combination with complex physical and biophysical processes affecting variations in hydroclimate and fuel conditions makes it difficult to directly connect wildfire changes over fire-prone regions like the western United States (U.S.) with anthropogenic climate change. Here we show that increasing large wildfires during autumn over the western U.S. are fueled by more fire-favorable weather associated with declines in Arctic sea ice during preceding months on both interannual and interdecadal time scales. Our analysis (based on observations, climate model sensitivity experiments, and a multi-model ensemble of climate simulations) demonstrates and explains the Arctic-driven teleconnection through regional circulation changes with the poleward-shifted polar jet stream and enhanced fire-favorable surface weather conditions. The fire weather changes driven by declining Arctic sea ice during the past four decades are of similar magnitude to other leading modes of climate variability such as the El Niño-Southern Oscillation that also influence fire weather in the western U.S.

Development and Evaluation of Chemistry-Aerosol-Climate Model CAM5-Chem-MAM7-MOSAIC: Global Atmospheric Distribution and Radiative Effects of Nitrate Aerosol.

An advanced aerosol treatment, with a focus on semivolatile nitrate formation, is introduced into the Community Atmosphere Model version 5 with interactive chemistry (CAM5-chem) by coupling the Model for Simulating Aerosol Interactions and Chemistry (MOSAIC) with the 7-mode Modal Aerosol Module (MAM7). An important feature of MOSAIC is dynamic partitioning of all condensable gases to the different fine and coarse mode aerosols, as governed by mode-resolved thermodynamics and heterogeneous chemical reactions. Applied in the free-running mode from 1995 to 2005 with prescribed historical climatological conditions, the model simulates global distributions of sulfate, nitrate, and ammonium in good agreement with observations and previous studies. Inclusion of nitrate resulted in ∼10% higher global average accumulation mode number concentrations, indicating enhanced growth of Aitken mode aerosols from nitrate formation. While the simulated accumulation mode nitrate burdens are high over the anthropogenic source regions, the sea-salt and dust modes respectively constitute about 74% and 17% of the annual global average nitrate burden. Regional clear-sky shortwave radiative cooling of up to -5 W m-2 due to nitrate is seen, with a much smaller global average cooling of -0.05 W m-2. Significant enhancements in regional cloud condensation nuclei (at 0.1% supersaturation) and cloud droplet number concentrations are also attributed to nitrate, causing an additional global average shortwave cooling of -0.8 W m-2. Taking into consideration of changes in both longwave and shortwave radiation under all-sky conditions, the net change in the top of the atmosphere radiative fluxes induced by including nitrate aerosol is -0.7 W m-2.

Black carbon deposited in Hariqin Glacier of the Central Tibetan Plateau record changes in the emission from Eurasia.

Black carbon (BC), by the combustion of fossil fuels and biomass, has profound effects on climate change and glacier retreat in industrial eras. In the present study, we report refractory BC (rBC) in an ice core spanning 1850-2014, retrieved from the Hariqin Glacier of the Tanggula Mountains in the central Tibetan Plateau, measured using a single particle soot photometer (SP2). The rBC concentration shows a three-fold increase since the 1950s. The mean rBC concentration was 0.71 ± 0.52 ng mL-1 during 1850s-1940s and 2.11 ± 1.60 ng mL-1 during 1950s-2010s. The substantial increase in rBC since the 1950s is consistent with rBC ice core records from the Tibetan Plateau and Eastern Europe. According to the predominant atmospheric circulation patterns over the glacier and timing of changes in regional emissions, the post-1950 amplification of rBC concentration in the central Tibetan Plateau most likely reflects increases in emissions in Eastern Europe, former USSR, the Middle East, and South Asia. Despite the low-level background rBC concentrations in the ice cores from the Tibetan Plateau, the present study highlights a remarkable increase in anthropogenic BC emissions in recent decades and the consequent influence on glaciers in the Tibetan Plateau.

Unraveling driving forces explaining significant reduction in satellite-inferred Arctic surface albedo since the 1980s.

The Arctic has warmed significantly since the early 1980s and much of this warming can be attributed to the surface albedo feedback. In this study, satellite observations reveal a 1.25 to 1.51% per decade absolute reduction in the Arctic mean surface albedo in spring and summer during 1982 to 2014. Results from a global model and reanalysis data are used to unravel the causes of this albedo reduction. We find that reductions of terrestrial snow cover, snow cover fraction over sea ice, and sea ice extent appear to contribute equally to the Arctic albedo decline. We show that the decrease in snow cover fraction is primarily driven by the increase in surface air temperature, followed by declining snowfall. Although the total precipitation has increased as the Arctic warms, Arctic snowfall is reduced substantially in all analyzed data sets. Light-absorbing soot in snow has been decreasing in past decades over the Arctic, indicating that soot heating has not been the driver of changes in the Arctic snow cover, ice cover, and surface albedo since the 1980s.

Recent intensification of winter haze in China linked to foreign emissions and meteorology.

Wintertime aerosol pollution in the North China Plain has increased over the past several decades as anthropogenic emissions in China have increased, and has dramatically escalated since the beginning of the 21st century, but the causes and their quantitative attributions remain unclear. Here we use an aerosol source tagging capability implemented in a global aerosol-climate model to assess long-term trends of PM2.5 (particulate matter less than 2.5 µm in diameter) in the North China Plain. Our analysis suggests that the impact of China's increasing domestic emissions on PM2.5 concentrations over the last two decades of 20th century was partially offset (13%) by decreasing foreign emission over this period. As foreign emissions stabilized after 2000, their counteracting effect almost disappeared, uncovering the impact of China's increasing domestic emissions that had been partially offset in previous years by reductions in foreign emissions. A slowdown in the impact from foreign emission reductions together with weakening winds explain 25% of the increased PM2.5 trend over 2000-2014 as compared to 1980-2000. Further reductions in foreign emissions are not expected to relieve China's pollution in the future. Reducing local emissions is the most certain way to improve future air quality in the North China Plain.